Patent GB-499911-A (GB)
Title: Improvements in or relating to apparatus for automatically signalling a fall of pressure in intercommunicating containers for fluids under pressure and interrupting communication between various containers
IPC: B60C23/04
Filed: 1937-10-28
Abstract: 499,911. Valves. CONTRI, G. D'O. Oct. 28, 1937, No. 29478. Convention date, Oct. 29, 1936. [Class 135] [Also in Group XXXIV] A device for automatically interrupting communication between pressure-fluid containers on fall of pressure in any one container, shown applied to normally - communicating twin pneumatic tyres, comprises a reciprocating member subject on one face to the pressure in the tyres and on the other face to an adjustable load, said member being adapted in one direction of movement to shut off communication between the tyres and to operate a signal, and in the other direction to open an escapevalve for the relief of excess pressure in either tyre. As shown, the tyres 11, 11<1> are connected by pipes 9, 9<1> to ducts 8, 8<1> which open at the rear face of a wall 62 formed in a cylindrical block 1. A flexible diaphragm 13, seated against a flange on the block 1, is clamped between the head of a block 15 and a spring 19, the pressure of which against the diaphragm is adjusted by means of a ring 17 threaded on the stem 15<1> of the block 15. A relief-valve 22, fitted in the outer end of the stem 15<1>, is arranged to be opened by abutment with an adjustable plug 20 when the pressure in the chamber 4 exceeds a predetermined amount to overcome the resistance of the spring 19. On fall of pressure in either of the tyres, the spring 19 moves the plug 15 on to the wall 62 to close the ducts 8, 8<1>. thereby preventing further escape of air from the undamaged tyre. At the same time, the plug 15 engages a nipple 40 of a switch U 'closing a circuit to operate an optical and audible signal-device. The ring 17 carries an arm 24, 241 which is adjustable on the casing 1 and is fitted with a pointer 50<1> arranged over the upper scale 64 of a dial 6. A pointer 7, actuated from a gauge 58 communicating with one of the ducts 8, 8<1>, tracks a lower scale 65 on the dial 6. In use, the handle 24 having been moved to set the pointer 50<1> at the pressure desired in the tyres, and with the plug 20 screwed back clear of the valve 22, the tyres are inflated through a nipple 56 leading to one of the ducts 8, 81. When the pressure indicated on the scale 65 slightly exceeds the desired pressure in the tyres, the plug 20 is screwed in until the valve 22 is just opened. On the resultant escape of air from the tyres, the spring 19 operates to move the plug 15 until, the tyres being at the desired pressure, the valve 22 is moved clear of the plug 20, the parts being then in the position shown in Fig. 2. Fig. 5 shows a preferred form of valve for use in the device (and for the tyres) in which the head 49 of the valve-plunger 69 is of polygonal form to afford a free passage of air through the stem. In modifications (not shown), the polygonal formation may be provided on the inner wall of the valve-casing ; or, either of the surfaces may be formed with longitudinal, helical, or inclined grooves.